A teenager who pleaded for his life as a gang armed with knives and swords chased and fatally stabbed him in the street was named yesterday as Hani Hicham Abou El-Kheir.

Witnesses described how the 16-year-old tripped while he was being pursued by a group of up to 15 youths close to home on a housing estate in well-heeled Pimlico and shouted “don’t do it” as he was surrounded. His mother rushed to the scene and had to be held back from a police cordon as medics battled in vain to save his life.

Police said last night they were keeping an open mind about the motive for the attack. A youth worker said there had been a concerted attempt by drug dealers to move into the area in recent months but although Hani’s name had been mentioned “on the periphery” of a gang, he had not been considered a significant or known member.

The attack shortly before 7pm on Sunday night took place close to Pimlico Tube station on a street flanked by multi-million pound houses and an estate of local authority tower blocks where Hani is believed to have lived with his mother.

One onlooker said that his killers ran away “as if nothing had happened” after having “jumped on him like a pack of dogs”. He was heard to plead “don’t do it” as the gang, many of whom witnesses said were wearing hoodies and bandanas across their faces, repeatedly stabbed him.

Hani, who is understood to be the first teenager murdered in London this year, was taken to hospital but died from his wounds two hours after the attack.

“My flatmate saw [him] swaying around for a few seconds then he collapsed between two parked cars. He saw three or four people running away up a side street, we believe they were the ones who attacked him,” 22-year-old Evgeny Onegin told the Independent today.

The University College London student of mechanical engineering said: “We rang the ambulance there was a lot of blood, he got stabbed really badly; there was a big pool of blood on the floor. You see kids messing around and there was another kid stabbed not far from here, but you still do not expect this type of thing.”

One witness said: “We were walking along and saw him running really fast but then he tripped. They had wide kitchen knives and other knives and they jumped on him like a pack of dogs. He was shouting ‘don’t do it’ but they just went ahead. One put a blade in near his ribs. Others then kicked him before just jogging off as if nothing had happened.”

The witness told the London Evening Standard: “They put their weapons in socks and then shoved them up their sleeves as they were going. Afterwards they looked calm, one looked straight at me as he was leaving which was scary — we thought they may go for us. We tried to help him as he was lying on the ground.”

A man who answered the door of Hani’s mother’s house today said that she was “broken hearted”. Steve Russell, 46, a project manager who was visiting a friend on a nearby estate, said he saw her run up to the cordon as paramedics treated her son. He said: “She was screaming with grief and shouting her son’s name but they wouldn’t let her through.”

A neighbour said Hani had always “seemed like a nice boy” to her. And family friend Mahmoud Abosiad visited the family and said: “He was a lovely boy. He did not deserve to end up on a slab.”

Rebecca Bartholomew, who lives a few doors down from Hani and his mother, said: “We never had any trouble. He had friends his own age and whether they were in trouble I don’t know. His mum is friendly too. They would say hello when we saw them.”

The principal of his former school, only a few hundred yards from where he was killed, said that pupils and staff were “deeply saddened” at his death. Jerry Collins said: “[We] extend our deepest sympathies to his family…Hani was a popular boy who conducted himself in an exemplary manner and will be much missed.”

Hani rejoined the Pimlico Academy in December 2011, having left once before in 2009. The school’s principal confirmed he was a pupil there until last summer. One school friend said Hani wanted to go to college. “He was a really calm, cool guy. I don’t know of any reason that anyone would have beef with him,” said the friend.

Police said officers were called to reports of a stabbing in at 6.50pm on Sunday. There were no arrests made and they appealed for witnesses. Hani Abou El Kheir was taken to south London hospital but died a few hours later. Officers cordoned off nearby streets and two forensic tents were in place today.

The area is known popularly as one of London’s most affluent but it also has areas of deprivation. Hani is thought to have lived in one of the numerous tower blocks lining the south side of Lupus Street, which runs near-parallel to the north bank of the River Thames. The houses facing the estate sell for millions of pounds.

A spokesman for the Metropolitan Police said: “A murder inquiry is now under way and an incident room will open in due course under detectives from the Specialist Crime and Operations Directorate.

“We must retain an open mind re the circumstances of the incident and any motive at this early stage.”

It emerged today that Hani’s name was flagged up to drugs workers last Wednesday. David Savizon, who works Westminster Council’s antigangs programme, said his name came up at a local meeting as someone who was “on the periphery of having some sort of contact with gangs or activity such as drugs”.

But he said: “He wasn’t deemed significant in terms of being in a gang. He was mentioned as someone on the periphery.”

A divided community: Pimlico's two faces

With its grand Regency houses and private gardens, Pimlico enjoys a reputation as one of central London's more genteel and privileged neighbourhoods, boasting a list of former residents from Sir Winston Churchill to Laura Ashley.

But like many other of the capital's well-heeled corners, the owners of multimillion-pound town houses co-exist with areas where the realities of life in tower blocks and low-rise estates can be altogether more harsh.

Crime levels in Pimlico, in the borough of Westminster, are about average for inner London but one local youth worker said the Churchill Gardens Estate, where Hani Hicham Abou El-Kheir lived, had become a drugs blackspot in the past year.

Yards from where monied residents, including many MPs who favour the area for its proximity to the Houses of Parliament, go about their business, children as young as 10 are paid “tens of pounds” to stash drugs and ferry them between dealers and buyers. Although gangs have yet to gain a stranglehold on the area, outreach workers say the wealth of Pimlico is regarded as “an opportunity” by dealers.

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